Responding to critics of the university as a bastion of PC, historian Levine (Black Culture and Black Consciousness) provides some worthy context. Curricula have always been evolving, he stresses, and historians long ignored non-Western and social history. The university, he adds, has also been evolving; however, his observation that the balkanized campus merely reflects endemic American fragmentation ignores how universities can act to further separatism or integration. Levine is most effective in explaining how the Great Books and Western Civilization courses developed to shape American identity after WWI, and how American literature entered the canon 50 years ago. Many historians, he notes, did not accept the ""melting pot"" notion and believed that ethnic distinctiveness could be prized; every criticism of integration today has been made before. Levine contends rationally that multicultural studies and ""the new historiography"" do not cause fragmentation but reflect it. Still, however accurate his argument may be in general, it has a detached air and will not fully engage those who decry campus excesses. 40,000 first printing; author tour. (Sept.)